After the attacks from inside calmed slightly, Shirou projected a black gunblade once more. Reaching his arm inside around the doorway, he pulled the trigger.
"Flashbang."
Chen, who had already been prepared, immediately turned around and faced away from Shirou.
Although she was confused by Shirou calling something fired from a gun a flashbang, she still avoided looking since he told her to.
After seeing the surroundings suddenly light up with a blinding flash, Chen gripped the standard Guard Department sword and charged in alongside Shirou.
The layout of the tenth floor had clearly been designed for an ambush. The entire place looked difficult to assault head-on.
But it did not matter. The invincible Shirou had already been unleashed.
To Shirou, those barricades and obstacles were no sturdier than tofu. Kanshou and Bakuya sliced through them in a few swift motions, cutting them into pieces.
Combined with using Noble Phantasms to open the assault and draw enemy fire, followed by the flashbang, dealing with these people did not require much effort.
"The number is smaller than expected. Could there still be people on the rooftop?"
After suppressing part of the group, Chen counted the people present and realized that even combined with those downstairs, the total still did not match the numbers Swire had reported.
Which meant there were still people they had not dealt with.
"Maybe they escaped upward the moment we opened the door?"
Glancing over, Shirou saw that these people also carried Reunion insignia. He chose not to dwell further on it and instead focused on a somewhat messy corridor nearby.
At the end of the corridor was a staircase leading to the rooftop. It was obvious that some people had fled upward.
Still, there was no rush. Projecting several massive swords to block the path, Shirou and Chen began clearing out the remaining enemies on the tenth floor while searching the area.
"Found it! It really is a signal jammer!"
After searching for quite a while, Chen found a bulky-looking device hidden in a corner.
This was the thing interfering with the Guard Department communicators the entire time.
"Let me see... nothing hidden inside. Should I destroy it directly, or does Officer Chen know how to operate it?"
Walking over, Shirou immediately used structural analysis on the internal mechanisms and found nothing suspicious.
So he asked for Chen's opinion, wondering whether she wanted to bring it back to the Guard Department or destroy it on the spot.
"Destroy it. The Guard Department has better equipment. We do not need this thing."
Chen spoke while stepping back a couple of paces to give Shirou room to destroy it.
The reason she had not recognized it immediately was because the jammer model was extremely outdated. If not for the red indicator light continuously flashing on it, she might have needed much longer to remember what it was.
"Understood."
After receiving Chen's instructions, Shirou directly split the machine in half.
After waiting several seconds, they finally turned the communicators back on and heard voices coming through the Guard Department channel.
"...Seriously, those two are way too reckless, are they not? They actually went up there with just the two of them? What a pair of Victorian profanity mixed with elegant Lungmen swearing."
The moment the communicator connected, both Shirou and Chen heard Swire's complaints.
Although she was clearly worried about them… the long stream of insults afterward still made the corners of their mouths twitch slightly.
"Ahem... Officer Shi, the communication channel has been restored," an unnamed Guard Department officer reminded her.
"How many times have I said this?! My name is not Shi! Call me Officer Swire!"
"Understood, Officer Shi. No problem, Officer Shi. Should we contact Officer Chen and Officer Wei first?"
Officer Wei: "..."
At that moment, Shirou suddenly understood Swire's feelings.
What kind of title was "Officer Wei"? Did they mean toilet paper?
"We are fine on our side. Aside from a portion of the people escaping to the rooftop, the other floors have already been cleared. Be careful of the ninth floor. There is a gas that accelerates Originium activity there, so remember to wear gas masks before entering."
Seeing Shirou's puzzled expression, Chen almost laughed. However, considering the current situation, she restrained herself and used the communicator to explain their status.
"Understood. Do you need us to bring gas masks and inhibitors up there?"
After reconnecting with Chen, Swire asked.
After all, this was a gas that accelerated Originium activity. Inhaling it could increase the density of Originium crystals in the blood and potentially cause Oripathy infection, so inhibitor injections were necessary.
"Bring both. I already injected one myself, but Shirou has not."
Glancing at Shirou, who was currently tying up the infected one by one, Chen replied.
She still had the gas mask on her face, but since it had been created through Shirou's abilities, there was no telling when it might disappear. Besides, she was not accustomed to this type of gas mask anyway.
Later, if there was an opportunity, she needed Shirou to upgrade some of the Guard Department's equipment...
"Hm?"
Suddenly feeling a chill run down his spine, Shirou tightened the rope in his hands and looked around cautiously. Then he realized he had pulled too hard and nearly strangled the unconscious infected person, whose eyes were bulging open.
Loosening the rope slightly, Shirou nodded in satisfaction and clapped his hands together.
Only after finishing all that did he finally take the time to listen to the communicator again.
The moment he heard that strange title earlier, he had mentally blocked out the communicator entirely and left everything for Officer Chen to handle.
After all, he was just a hired worker. It was perfectly fine for him not to deal with these things.
"Once they finish clearing the gas on the ninth floor, they will come up and regroup with us. Until then, let us rest."
Seeing that Shirou had finished up, Chen briefly explained the current situation.
As for the people on the rooftop, they could ignore them for now. The troublesome signal jammer had already become scrap metal, meaning they could simply use drones to deal with those people above. Swire was already arranging it.
"I thought you were going to say we should storm the rooftop and wipe everyone out in one go."
After hearing Chen's words, Shirou pulled over a chair, sat down, and leaned against the backrest.
He had already prepared himself for another round of fighting, yet Officer Chen was actually suggesting they rest first?
Hearing the word "rest" come out of her mouth felt strangely unnatural to him.
"That is because we still have to wait for the others to clean up the hazardous gas. We might as well use the time to rest. Earlier, the jammer prevented us from knowing what was happening outside, so I chose a more aggressive approach."
Chen pulled over another chair and sat across from Shirou, taking the chance to rest while explaining why she had made those command decisions earlier.
"That makes sense... the workload these past two days really has been insane."
Shirou casually agreed, though what occupied his mind more was the inhibitor injection Chen used earlier.
After calming down and thinking it over, Shirou became slightly less certain that Chen was infected, though suspicion still remained.
Still, he was not about to ask her directly. That would have been rather rude.
Besides, whether she was infected or not made no difference to Shirou. He would not distance himself from her because of it. He would continue interacting with her the same as always.
"Exactly."
Noticing that Shirou seemed distracted, Chen did not say much more.
She herself was exhausted. Between physical fatigue and the effects of Oripathy, she felt her condition was terrible.
Just dealing with three or four people earlier had already left her short of breath. That should not have happened.
It would probably take Char Siu Cat more than ten minutes to get up here, so she might as well rest during this time.
Thinking that, Chen slowly narrowed her eyes.
"..."
Watching Officer Chen sitting across from him with her eyes slowly closing, clearly beginning to doze off, Shirou's expression shifted from confusion to surprise, and finally to complete shock.
What exactly was he seeing?
Officer Chen was actually dozing off in the middle of an operation?
That same Officer Chen who always kept a stern face and maintained a serious expression at all times?
At that moment, Shirou's emotions were complicated. It was probably comparable to witnessing Exusiai and Croissant voluntarily studying subjects they did not even understand.
Unfortunately, the Officer Chen in front of him truly had fallen asleep, while Exusiai and Croissant voluntarily studying was something that would never happen.
Both of them were the type to cram at the last minute.
Looking at Officer Chen dozing off while hugging the scabbard of her standard sword in both hands, Shirou could only slowly stand up and walk to the side.
He did not have a hobby of staring at sleeping people. Besides, now that she had fallen asleep, the responsibility of keeping watch naturally fell to him.
At present, the greatest danger was the staircase leading to the rooftop. Shirou had already blocked it off with a large number of Noble Phantasms. If anyone wanted to come through, they would first have to destroy those weapons.
The next concern was... the windows.
Shirou had not forgotten that the enemy possessed drones. However, he had not heard the sound of any drones flying nearby, so it was probably fine for now.
Lastly, there was the entrance...
Still, Shirou had a feeling that the people who escaped to the rooftop definitely had some kind of backup plan. There was no way they would simply sit there and wait to die.
Thinking of this, Shirou placed his hand against the wall, magical circuits appearing across his right hand.
"Trace on"
"The walls are fine, the floor is fine, the cabinets and tables are fine as well..."
Unlike before, Shirou carried out a far more thorough inspection this time.
Fortunately, he did not find anything strange, which eased his worries slightly.
Extending his analysis upward, Shirou could clearly sense dozens of people above them, though he could only tell they were there and not what they were doing.
After informing Swire about this, she said she was already arranging a drone swarm and told him and Chen not to worry too much and to get some proper rest.
Hearing Swire's words, Shirou felt somewhat conflicted.
In a certain sense, Swire and Officer Chen actually seemed rather close.
Although they constantly argued and even got physical at times, when things truly mattered, they still worried about each other immediately.
"..."
Something was wrong.
Shirou suddenly sensed an abnormality.
The flow of air inside the room had suddenly become strange, as though it was gathering toward a specific point.
Turning around, Kanshou and Bakuya appeared in Shirou's hands.
He could clearly see that the center of the gathering airflow was the group of infected people he had tied up earlier.
"Officer Chen!"
Shirou had no idea what this meant, but waking Chen immediately was definitely the correct decision.
The moment Shirou shouted, Chen instantly opened her eyes and noticed the abnormality in the room as well.
The airflow had already become extremely obvious. Trash and loose sheets of paper floated around the room.
"Originium Arts? At this scale... are they burning through their own lives to cast it?"
Compared to Shirou, Chen immediately recognized that one of the infected was using Originium Arts, with the Originium crystals in their own body serving as the casting medium.
After identifying the source of danger, Chen immediately drew her standard sword and rushed toward the infected person at incredible speed.
Her sword thrust forward, piercing through the infected person's right chest.
Yet the person showed no reaction whatsoever and remained unconscious.
Seeing this, Chen realized just how serious the situation had become.
"Everyone retreat! These people are all traps!" Chen shouted into the communicator.
Downstairs, Swire, who was supervising the removal of the dangerous gas, immediately turned grim after hearing Chen's warning. Nevertheless, she followed the order and rapidly evacuated the others.
At the same time, Shirou immediately equipped his Mystic Code and rushed forward, pulling Chen behind him.
Even without Chen's command, Shirou had already realized how bad the situation was.
The Originium crystals on those people's bodies were spreading at a visible rate, climbing from their necks up to their faces in an incredibly grotesque manner.
Seeing this scene, Shirou was already prepared to jump out the window at any moment.
If this continued, those people would likely become sources of Originium contamination.
To put it bluntly, they would become natural Originium explosives.
The kind with immense power and long-lasting contamination.
He had read about this in books before. It was also one of the primary reasons infected people were so heavily feared and rejected.
Although they had not yet reached that stage, if things continued like this, it was only a matter of time.
"Get ready... we are jumping down."
Seeing the situation deteriorating rapidly, Shirou decided to use the worst-case evacuation route.
Slowly retreating down the stairs was unrealistic. Going upward was equally dangerous since there was no telling what kind of ambush waited above. Moreover, this was Shirou's first time encountering such a situation, so he had no idea how powerful the explosion of dead infected individuals could become.
But one thing was certain: if Officer Chen remained here any longer, she would definitely become a severe-stage infected patient, even while wearing a gas mask.
The infectiousness of airborne Originium dust after detonation was extremely high. Even the smallest wound was enough to infect someone immediately.
Shirou did not dare gamble.
At the very least, he would never gamble with someone else's life.
Under normal circumstances, such explosions only occurred some time after death.
However, the terrifying speed at which the Originium crystals were spreading meant there was definitely something unusual inside these people's bodies. Under such extreme circumstances, exploding immediately was not impossible.
"Jump?"
Chen, who had already prepared herself to retreat downstairs, was suddenly lifted into Shirou's arms. Watching him smash the window, she instantly understood what he meant by "jump."
"Wait a second—"
Before Chen could stop him, Shirou leapt straight out the window.
Feeling the fierce wind from ten stories up, Officer Chen could not help but curse:
"You damned bastard, Shirou!"